Rotary pump



Patented Jan. 3, 1950 ROTARY PUMP Laurits Dinesen and Lawrence J. Olson, Minneapolis, Minn., assignors to Perfection Manufacturing Corporation, Minneapolis, Minn., a corporation of Minnesota Application February 24, 1948, Serial No. 10,534

Our invention relates to rotary pumps or the reciprocating vane type and, more particularly, to pumps of the stated type involving reciprocating vanes of resilient material such as rubber or synthetic rubber.

The primary object of our invention is the provision of a pump of the character described, which is capable of producing relatively high fluid pressures. In accordance with the invention, this is achieved inexpensively by a novel design of reciprocating vane, producing an improved fluid pressure seal between the reciprocating vanes and the cooperating wall of the pump chamber.

Another important object of our invention is the provision of a pump having a relatively permanent rotor having readily replaceable, inexpensive vanes therein.

Another object of our invention'is the provision of a novel sealing means for the rotary shaft.

The above and still further objects of our invention will become apparent from the following detailed specification, appended claims, and attached drawings.

Referring to the drawings, wherein like characters indicate like parts throughout the several views:

Fig. l is a view in end elevation of our novel Fig. 2 is an enlarged end elevation of our novel pump with one of the end wall elements removed;

Fig. 3 is an enlarged vertical section taken on the line 3-3 of Fig. 1;

Fig. 4 is a horizontal section, taken substantially on the line 4-4 of Fig. 1;

Fig. 5 is a view in elevation of the interior of one of the end wall elements;

Fig. 6 is an enlarged axial section through a sealing member used in accordance with our invention; and

Fig. '7 is a view corresponding to Fig. 2, but showing a slightly modified form of our invention.

Referring to Figs. 1 to 6 inclusive of the drawings, the numeral I indicates, in its entirety, a pump housing preferably metallic in nature. The housing I defines a cylindrical chamber 2, the circular wall of which is indicated by the numeral 3. A pair of end wall elements 4 define end walls 5 of the chamber 2 and are provided with inlet and outlet recesses 6 and 1 respectively. The housing I is further provided with opposed bosses 8 and 9 respectively which are threaded to receive fluid conduit means in the nature of pipes or the like II, and which define inlet and outlet passages H and I2 respectively. As shown, particularly by reference to Fig. 4, the inlet passage 2 Claims. (Cl. 103-136) II is bifurcated to provide communication with the recesses O in the end wall elements 4. The outlet passage I2 is similarly divided to provide communication therebetween and the recesses I in the end wall elements 5. It will be noted that g the recesses 6 and I communicate with the cylindrical chamber 2 and form a passage therebetween and the inlet and outlet passages ii and I2 respectively. a It will be further noted that the inlet and outlet passages II and I2 are circumferentially spaced about the axis of the cylindrical chamber 2 and are in axial alignment one with the other. The end wall elements are secured to the body I by machine screws or the like l3, and sealing gaskets H are interposed between the main body I and the end wall element 4.

A rigid rotor element l5, also preferably formed from metal or the like, is mounted for rotation within the chamber 2 by means of a shaft i8, fast therein, and journalled in opposed bearing bosses ll of the end wall elements 4. It will be seen, particularly by reference 'to Figs. 2 and 3,

.that the rotor I5 is eccentrically disposed with respect to the chamber 2 and that opposite side surfaces l8 thereof have close working engagement with the inner surfaces or end walls I of the end wall elements 4.

The rotor I5 is provided with a plurality, shown as being four in number, of circumferentiallyspaced radially-extended channels IS, in each of which is mounted for radial sliding movements a preferably flexible resilient vane 20 having at its radially outer end, a lip 2| which projects angularly therefrom in the direction of rotation of the rotor. The inner and outer surfaces 22 and 23 respectively of the lip 2i converge toward the forward edge thereof, the inner surface 22 being relatively fiat and at substantially right angles to the body of the vane 20, and the outer surface 23 thereof being cross-sectionally arcuate in form-the arc thereof corresponding substantially to the arc of the circular wall 3 of the chamber 2. a

It will be observed, particularly by reference to Fig. 2, that, at its periphery, the rotor I5 is provided with a plurality of relatively flat surfaces 24, one each of which extends between outer ends of adjacent channels I9. It will further be observed that, preferably and as shown, the walls of the channels adjacent the lips 2| are of less height than the opposing walls of said channels, said higher wall of each channel I! backing up and supporting the resilient vanes 20 and preventing undue distortion thereof.

means ticed with a cross-sectionaliy circular rotonprovidlng convex arcuate surfaces intermediate the vanes 20, we have found, in practice, that greater eiilciency can be obtained by diametrically reducing the segments of the rotor intermediate the increase the chamber spaces between adjacent vanes 20 and beneath the forwardly-projecting lips 2| thereof. In the preferred embodiment of the invention, this is accomplished by providing the rotor with flat surfaces 24 intermediate adjacent vane channels is. In either event, however, it should be obvious that fluid drawn into the chambers 2|, between the vanes 20 from the inlet passages H, has an initia1 impact of considerable force against the-inner surfaces 22 of the lips 2|, thereb forcing the lips 2| and vanes 23 radially outwardly to cause the arcuate surfaces 23 of the lips 2| to make tight sealing engagement with the chamber wall 3. It will be clear that fluid pressure built up within the chamber 2' between the vanes 20 will be applied to only the inner surfaces 22 of the vane lips 2| and in a generally radially outward direction which will serve to force the lips 2| and vanes 20 radially outward into tighter sealing contact wtih the cylindrical wall 3 of the pump chamber 2 as the pressure increases. In short, the pressure within the chambers 2' is utilized to increase the sealing pressure betweenthe vanes 20 and the wall 3.

It will be observed that the opposed end wall elements or caps 4 are provided with annular recesses 25 which are concentric with the shaft l6 and terminate in flat end walls 26. Contained within each of the recesses 25 is a bushing or sleeve 21. The sleeve 21 may be made of any suitable flexible resilient material, such as synthetic rubber or the like, and is provided at one end with a radially-projecting circumferentiallyextended flange 28 which is preferably integrally formed therewith. The sleeves 21 are of a size to flt snugly on the shaft i6 so as to rotate therewith, and have their ends opposite the flange 26 abutting the opposed side surfaces l8 of the rtor |5.The bushings 21 are of greater length than the distance between the flat end walls 26 of the recesses 25 and the side surfaces i8 of the rotor l5. It will be seen, particularly by reference to Fig. 6, that the flanged ends of the bushings 21 are provided with concave faces 29 which are disposed adjacent the end walls 26 of therecesses 25. When the end wall elements 3 are pulled tightly against the main body I. the flanges '26 of the bushings 21 are forced in a direction axially of the bushing to a point where the concave surfaces 29 are compressed against the flat end walls 26 of the recesses 25. Fluid within the pump which might enter the recess 25 under pressure will tend to force the flanges 28 against the end walls 26, whereby to still further seal the interior of the pump from leakage around the shaft l6.

While we have shown the recesses 25 as being formed in the end wall elements 4, it should be clear that suitable recesses could be provided in the rotor element 5. The important thing is that the depth of the recesses 25, irrespective of whether it be located in the rotor element IE or in the side wall element 4, is slightly less than the maximum length of the resilient bushing 21, corresponding approximately to the minimum length thereof, measured along the shaft l6.

In the modified form of the invention, illustrated in Fig. 7, the pump housing, inlet and outadJacent vane-containing channels I! to thereby 4 let bosses thereon, fluid conduit means leading thereto and therefrom, and rotor chamber are all identical to the structure illustrated in Figs.

1-8 inclusive and bear the same reference characters with prime marks added. The structure of Figs. 1-6 inclusive .illustrates a unidirectional pump, whereas Fig. 7 illustrates a pump that may be run in either direction. In the pump of Fig. 7, we provide a rotor 30 fast on a shaft 3| joumalled in end wall elements in the manner of the structure of Figs. l-6 inclusive and having a plurality of radially outwardly-opening axially extended channels 32 therein. Mounted for radial sliding movements in each of the channels 32 is a flexible resilient vane 33 provided at its outer end with a pair of opposed flexible resilient lips 34 which project angularly therefrom in the same manner as the lips 2| of the vanes 20, illustrated in the preferred embodiment of the invention. The rotor 3|! is shown as having fiat peripheral surfaces 35; and the medial plane of each channel 32 extends through the point of intersection of two adjacent of the flat surfaces 35. .The action of the pump of Fig. '1 is identical to that of Figs. 1-6 inclusive and only one lip 34 of each vane 33 will be utilized at any particular time for sealing engagement with the chamber wall 3, the lip so utilized being the one which projects forwardly in the direction of rotation of the rotor 29.

As is necessary with pumps of the type herein set forth, provision is made for displacement of fluid in the channels l9 radially inwardly of the vanes 20. This provision is in the nature of a plurality of passages 36 extending diametrically through the rotor i5 and shaft 3| and connecting diametrically opposite channels i9. Radially inward movement of any one of the vanes 20 and corresponding radially outward movement of the opposed vane 20 will cause the fluid in the channel IQ of one thereof to flow through the passages 36 connected therewith to the channel IQ of the other thereof. Thus, impedance of radial movements of the vanes 20,-due to differential and pressure within the channels I9, is eliminated.

Our invention has been thoroughly tested and found to be entirely satisfactory for the accomplishment of the objectives set forth; and, while we have shown a preferred embodiment and a single modification of our invention, it will be understood that the same is capable of further modification without departure from the spirit of the invention as defined in the claims.

What we claim is:

1. In a device of the class described, a housing having a cylindrical pump chamber therein, circumferentially-spaced inlet and outlet passages leading respectivelyto and from said chamber, a rotor journalled in said housing and eccentrical- 1y positioned within said chamber, a plurality of circumferentially spaced radially outwardlyopening channels in said rotor, and a vane loose- 1y mounted in each of said channels for radial sliding movements, the peripheral surfaces of said rotor intermediate said channels being flat, the rear walls of said channels with respect t the direction of rotation of the rotor being higher than the front walls thereof.

2. The structure defined in claim 1 in which said vanes at their radially outer ends are provided with'integral rubber-like lips which project angularly therefrom in the direction of roigtion.

LAURITS DINESEN. LAWRENCE J. OLSON.

(References on following page) REFERENCES CITED Number 1,980,404 The following references are of record in the 2015 501 UNITED STATES PATENTS 5 2,433,484

Number Name Date 1,339,723 Smith May 11, 1920 Number 1,369,380 Bogdanofl Feb. 22, 1921 31,237 1,521,226 Bogdanofl Dec. 30, 1924 10 112,736 1,651,336 Wissler Nov. 29, 1927 147,225 1 Name Date Harman et a1 Nov. 13, 1934 some Sept. 24, 1935 Yauch Nov. 10, 1942 Roth Dec. 30, 1947 FOREIGN PATENTS Country Date France Sept. 21, 1926 France 1876 Switzerland Aug. 1, 1931 

